If you describe someone, especially an adult, as childish, you disapprove of them because they behave in an immature way.
例句
...Penny's selfish and childish behaviour...彭妮自私、幼稚的举动Don't be so childish.别这么不懂事。
英汉词典释义
adj.
孩子的,孩子气的,孩子所特有的
The little girl spoke in a high childish voice.这个小女孩用尖尖的童声讲话。We danced around with childish delight.我们像孩子一样欢快地围在一起跳舞。When a girl grows up,she puts childish habits on the shelf.一个女孩长大后,就丢掉了孩子习气。
幼稚的
A childish idea like that can be amusedly tolerated.像那样幼稚的想法可以一笑置之。We eventually ran out of patience with his childish behaviour.我们终于对他幼稚的行为忍无可忍。You would be laughed out of court with such a childish question.你提出这样幼稚的问题,会被人一笑置之的。He never dreamed that his request would be laughed off as a childish fancy.他做梦也没想到,他的要求被当成幼稚的幻想而一笑置之。